Program Multiplier of SKs, Semiautonomous Knowbots not Saeder-Krupp Options

[Moon-Hawk]

I know PCs aren't supposed to be able to design SKs. It's stated very clearly.
But we do know that it takes a team of a half dozen top programmers to do it, and that you can't use a programming suite. (see Matrix pg. 147)
We know they follow the same rules as smart frames and agents. In fact, the only game mechanical thing we don't know is the programming modifier, I assume because the designers are afraid (rightly so) that if you stat it, PCs will make it. Just like if you stat an IE, PCs will kill it.
But even so, if PC's are allowed to make a rating 14 Agent, then why not a rating 2 SK? I much prefer things to be impossible (or unfeasible) within the rules rather than impossible by fiat.
So c'mon, what would it be?
For quick reference, Smart Frames are 6, Agents 10, Black IC 12-25
I know there are a lot of choices in the poll; I'm hoping to see something bell-curve-ish.

edit: Lethal Black IC is multiplier 25, as per the Matrix errata pg 165.